Adjustable screeding machines



Jan. 21, 1964 D. F. NEIL 3,118,353

ADJUSTABLE SCREEDING MACHINES Filed Oct. 19, 1960 2 Sheets-Sheet l l vv U ATTORNEY Jan. 21, 1964 D. F. NE1L.

ADJUSTABLE s cREEDING MACHINES 2 Sheets-Shea?I 2 Filed 00t- 19, 1960 I wif United States Patent O 3,118,353 ADJUSTABLE SCREEDING MACHINES Donald Francis Neil, 627 1st St., Saskatoon, Saskatchewan, Canada Filed ct. 19, 1960, Ser. No. 63,592 Claims priority, application Canada June 14, 196i) l Claims. (Cl. 94E-45) This invention relates to concrete nishing machines and is directed more particularly to improvements in selfpropelled screeds for striking oi and vibrating slabs of freshly poured concrete.

Road iinishing machines having track engaging wheels are presently in wide use, these machines generally being cumbersome and diicult to move about from job to job. The present invention seeks to provide a mechanical concrete finishing machine which is simple and economical to construct and assemble and which provides greatly improved flexibility of screed adjustment including provision for tilting the working area of the screed with respect to a horizontal plane. Apparatus according to the invention is especially adaptable to use with various structural beam forms serving as screeds, which may be any desired length.

The invention essentially consists in the assembly of a pair of end frame panels riding on a pair of steerable track-engaging wheels, together with a transverse screed having the form of a structural steel beam of any suitable length whose ends are removably secured in sockets attached to the panels, the sockets being supported in adjustable ways for regulating the height and angular relationship of the screed with respect to a concrete mass.

In carrying the invention into eiiect each of a pair of end frame panels has one of its support wheels powered and the pair are ganged for joint steering along a horizontal track adjoining a concrete slab, and a screed beam having any suitable cross section is clamped by its ends in recesses of complementary cross section in an adjustable beam support member suspended in each frame. The beam support member is preferably arranged for vertical guided movement along ways which are themselves pivotable in the end frame panels about an axis parallel with the beam, whereby the angle of contact of the working edge or face of the screed may be adjusted with respect to the finished concrete surface. Any suitable means to vibrate the beam to improve the concrete slab may be attached, such apparatus per se forming no part of the present invention.

The invention may be the better understood from a study of a preferred embodiment thereof described hereinafter and illustrated by the accompanying drawings, in which:

FIG. l is a perspective view of a mechanical nishing machine for road slabs, constructed according to the invention;

FIG. 2 is a rear elevational view of one end oi the iinishing machine of FIG. l;

FIG. 3 is a perspective view of a screed support member suspended in a vertical guideway;

FIG. 4 is an end elevational view of the machine of FG. l; and

FIG. 5 is an elevational cross section through a screed taken along the line 5-5 of FIG. 1.

Referring to the drawings, the machine comprises a pair of vertical end frame panels 1l, l2, each consisting of inverted U-shaped tubular elements having horizontal portions 13, 14 and spaced apart vertical elements 15, 16, and 17, 18. These elements are each braced by a pair of vertically spaced horizontal angle section braces designated 19, 20, and 21, 22, which are preferably welded upon the outer sides of the vertical tubular elements to provide a rigid yet light frame panel structure.

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The machine is adapted to ride on the side forms 23 and 24 enclosing a concrete strip 25, being provided with wheels 26, 27 supporting the U-legs 15 and i6, and wheels 28, 29 supporting -U-legs 17, i8. The wheels have cylindriform running faces riding upon wood tracks 30, 31, the latter being conveniently realized from lengths of structural lumber of conventional sizes. While in the embodiment illustrated flanges have not been provided it is to be understood that alternatively flanges may be formed on one or both edges of either or both wheels of an end frame panel, as desired. Smooth faces are preferred particularly when the track guide means described hereinafter are employed with level tracks.

Each of the four wheels is journalled in respective U-shaped brackets 32, 33, 34, and 35, which have integral vertical bosses such as 36 extending from their upper portions, as shown in FlG. 2, each boss being fitted for rotation about a vertical axis in the tubular end frame legs. The lower ends of the latter rest upon the relatively rotatable bracket collars 37, 38, 39 and 4b. One bracket of each pair of wheel brackets such as 32 and 34, is iitted with xed axles 4l and 42. respectively on which the wheels 26 and ZS freely turn. The rear wheels 27, 29 of the wheel pairs are driven by aides 43, 44 coupled to powered driving means, which may conveniently be electric motor drives 45, 46, employing battery or mains power fed to their motors by suitable connectors and controls (not shown). Axles 43, 44E are each journalled for rotation in the lower ends oi the wheel support brackets 33, 35, the latter having their inner vertical members doubled by a support plate for attaching the motor and drive.

For the purpose of guiding the wheels of each wheel pair for tracking along tracks 36B or 3l, laterally projecting lugs 47, 4S and 49, Sil, secured to respective brackets as by welding, are connected in pairs by side links 5l, 52, so that each wheel pivots about a respective vertical axis and turns through the same angle. The links are preferably engaged by their downwardly extending hook ends engaged pivotally in circular apertures in lugs 47, 4S, and 49, 5i) so that the wheels may be released for independent steering.

Front wheel brackets 32 and 34 are each connected to U-shaped forwardly extending guide arms 53, 54, the latter being hingedly connected to track-engaging riders 55 and $6. Each rider has a track slide, respectively marked 57, 58, formed adjacent its forward end, and carries clamps adjustably holding side stops 59, 6d fitted to loosely engage opposite sides of the track. Each guide arm serves to align the axles so that the end frame panel supported thereby moves accurately along the track. Preferably only the inner vertical faces of tracks 3d and 3l. are made effective to guide the arms 53, 54, by arranging that spring d2 secured under tension between the outer vertical members of brackets 32 and 34 and the frame, as shown in FIG. 4, biases side stop titl to press against its adjacent track face.

The machine carries a screed 6l having its ends supported in pivoting guides 62, 63, suspended respectively from pivots 64, centered in upper transverse braces 19, 20.

Each vertical guide is pivotable throughout an angular range extending about 10 forwardly and rearwardly of the vertical, a pin 9G fixed to the outer face of each passing through arcuate slot 99 in lower transverse brace 21 and carrying suitable clamp means for holding a hanger in a desired angular relationship with respect to the end frame. A lead screw ed journalled in and axially restrained in bracket 67 xed on the end frame engages a threaded lug 68 fast to the exterior face of the vertical guide channel, whereby rotation of setting handle 69 fast to the lead screw determines the angular position of the hanger.

Pivoting guides 62 and 63 comprise relatively wide vertical channels having inwardly turned lateral anges 70, on which are secured the opposed pairs of narrow guide channels 71, 72, forming ways along which the side edges of screed support members 73, 74 are guidedly reciprocable. Vertical lead screws 75, 76 have their lower ends pivotably connected as by pins 77, 78 with the up er margins of respective screed support members, and their upper ends freely passed through the horizontal frame elements 13, 14 of the end frame panels. Spherical collars 79, 80 support the weight of each lead screw and its connected load, interposed between the underside of height setting hand wheels 81 and 82 and respective horizontal tubular frame portions 13, 14. The hand wheels serve to regulate the vertical positions of members 73, 74, thereby controlling the relative position of screed beam 61 with respect to the level of tracks 30, 31, while a degree of resilience is provided by the suspension system thus realized to minimize damping of forced vibrations imparted to the screed.

Each of members 73, 74 is formed with a socket such as 83 for laterally receiving and clamping fast an end of the screed beam, as may best be understood by reference to FIGS. 3 and 5. The socket cross section is formed to receive a horizontal upper iiange and a vertical web in the median plane of the liange. Socket 83 is formed in a structure comprising a braced, inwardly extending horizontal channel portion 84 xed to support members 73, 74, and carries downwardly turned flanges, from whose margins a pair of integral right angle sections are supported to present horizontal edges 85, 86 turned upwardly and spaced below the underside of channel 84. The

screed I-beam top iiange 91 is received in the socket 83 above the edges 85, 86 and under the horizontal portion of channel 84, as shown in FIG. 5.

Clamping bolts 87 threaded into the wall of channel S4 press against the upper flange 91 of screed 61, while opposed lateral clamp bolts 88 threaded through opposed vertical flanges of channel S4 secure the screed against lateral motion.

It will be apparent that T `and H section beams of rolled structural steel may be similarly supported in socket 83, and that numerous other sections may be employed with hangers having sockets formed to receive their ends to be similarly clamped.

The erection or dismantling of the concrete finishing machine and its operation may be effected simply by two men, or even one man may readily operate it with suitable controls. Any desired length of self-supporting screed beam may be employed. Each screed support member 73 and 74 is first lowered sufficiently so that its socket is aligned with the upper iiange 91 of the screed beam, and each end frame panel is thereupon rolled into a position adjacent a beam to engage the ends. Where necessary the wheels may previously be turned at right angles to the panels with links 51, 52 released, although it is entirely feasible to lift each panel bodily into position. Upon clamping of the beam in its sockets, the wheels are then linked for joint steering and the screed raised. The entire assembly is then steered to move to the work,

propelled under its own motive power, any suitable temporary track being laid.

Any conventional form of vibrator device 93 may be mounted midway along the screed beam to eiect a desired degree of vibration, for example the device may be electrically energized as shown by application of suitable potentials to leads 95.

I claim:

1. In a concrete smoothing machine, the combination of a pair of wheeled travelling frames spaced apart perpendicular to the direction of advance of said frames, a screed beam, movable support means at opposite ends of said screed beam adjustably mounted on said frames, vcrtical guide means pivotally mounted about a common transverse axis on said frames with said support means being guidedly movable in said guide means for vertical and radial movement relative to said pivot axis, cach said support means including means for independently controlling vertical displacement of an end of said screed beam within said guide means, and means for controlling forward and rearward arcuate displacement of said guide means about said pivot axis.

2. A concrete smoothing machine as in claim l wherein said vertical guide means comprise a vertically elongate channel member having vertical guide ways formed therein, pivot pins securing an upper end of each channel member in a respective travelling frame for pivotal movement about said pivot axis, and said movable support means comprise a slide reciprocable in said guide ways and con trollable in vertical position by lead screw means having one end axially restrained in said frame for suspending said slide from said frame, said slide having a screed receiving socket formed therein to extend laterally in opposed relation with a like socket in the opposed frame.

3. A smoothing machine as in claim 1 wherein cach of said travelling frames comprise a braced tubular frame formed in inverted U-shaped having vertical side legs and a horizontal transverse upper portion joining said side legs, a pair of steerable support wheels carrying respective side legs and adapted to ride along a guide track, and wherein steering link means are disconnectably connected between each said pair of wheels for joint steering thereof, a forward wheel of each wheel pair having a forwardly extending steering arm adapted to ride along said track to align said pair of wheels in tracking relation.

4. A machine as claimed in claim 3 wherein said wheels comprise brackets having transverse axles and a vertical pivot axle, a forward wheel of each pair having a transverse axle xed in a bracket and journalling said wheel, the rearward wheel of each pair being fixed for joint rotation with a powered transverse axle journallcd in the associated bracket, said powered axle having motive power drive means coupled therewith.

References Cited in the file of this patent UNITED STATES PATENTS 413,846 Chambers Oct. 29, 1889 2,187,080 Heltzel Jan. 16, 1940 2,754,732 Beyer July 17, i956 FOREIGN PATENTS 70,457 Denmark Dec. 27, 1949 

1. IN A CONCRETE SMOOTHING MACHINE, THE COMBINATION OF A PAIR OF WHEELED TRAVELLING FRAMES SPACED APART PERPENDICULAR TO THE DIRECTION OF ADVANCE OF SAID FRAMES, A SCREED BEAM, MOVABLE SUPPORT MEANS AT OPPOSITE ENDS OF SAID SCREED BEAM ADJUSTABLY MOUNTED ON SAID FRAMES, VERTICAL GUIDE MEANS PIVOTALLY MOUNTED ABOUT A COMMON TRANSVERSE AXIS ON SAID FRAMES WITH SAID SUPPORT MEANS BEING GUIDEDLY MOVABLE IN SAID GUIDE MEANS FOR VERTICAL 